Generic Type[T] function argument rejected as base class

Bug Report

Since https://github.com/python/mypy/issues/5865 was fixed, the following code now type checks:

from typing import Any, Type


def f(typ: Type[Any]) -> Type[Any]:
    class C(typ):
        pass

    return C

However if we make the superclass generic, it doesn't type check anymore which I would expect it to do.

To Reproduce

from typing import Type, TypeVar

T = TypeVar("T")


def f(typ: Type[T]) -> Type[T]:
    class C(typ):
        pass

    return C

Actual Behavior

mypy_return_type.py:7: error: Variable "typ" is not valid as a type  [valid-type]
mypy_return_type.py:7: note: See https://mypy.readthedocs.io/en/stable/common_issues.html#variables-vs-type-aliases
mypy_return_type.py:7: error: Invalid base class "typ"  [misc]
Found 2 errors in 1 file (checked 1 source file)

Your Environment

• Mypy version used: 1.0.0+dev.e9f5858c44b61c2d02819940debe3c31d099f9d5
• Mypy command-line flags: mypy mypy_return_type.py
• Mypy configuration options from mypy.ini (and other config files): None
• Python version used: 3.10.9

Riproduci il report con l’esempio generico Type[T] fornito usando mypy mypy_return_type.py, quindi traccia il percorso del controllo dei tipi per le espressioni di variabili usate come classi base e confrontalo con il caso non generico Type[Any]. Il lavoro è completato quando l’esempio generico supera il controllo dei tipi senza gli errori valid-type e Invalid base class, mantenendo il proprio tipo di ritorno Type[T].